src/protocols/user_directed_commissioning/UserDirectedCommissioningServer.cpp - third_party/github/project-chip/connectedhomeip - Git at Google

 /*
  *
  *    Copyright (c) 2021-2022 Project CHIP Authors
  *    All rights reserved.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
  *    You may obtain a copy of the License at
  *
  *        http://www.apache.org/licenses/LICENSE-2.0
  *
  *    Unless required by applicable law or agreed to in writing, software
  *    distributed under the License is distributed on an "AS IS" BASIS,
  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *    See the License for the specific language governing permissions and
  *    limitations under the License.
  */

 /**
  *    @file
  *      This file implements an object for a Matter User Directed Commissioning unsolicited
  *      recipient (server).
  *
  */

 #include "UserDirectedCommissioning.h"
 #include <lib/core/CHIPSafeCasts.h>
 #include <system/TLVPacketBufferBackingStore.h>

 #include <unistd.h>

 namespace chip {
 namespace Protocols {
 namespace UserDirectedCommissioning {

 void UserDirectedCommissioningServer::OnMessageReceived(const Transport::PeerAddress & source, System::PacketBufferHandle && msg)
 {
     char addrBuffer[chip::Transport::PeerAddress::kMaxToStringSize];
     source.ToString(addrBuffer);
     ChipLogProgress(AppServer, "UserDirectedCommissioningServer::OnMessageReceived from %s", addrBuffer);

     PacketHeader packetHeader;

     ReturnOnFailure(packetHeader.DecodeAndConsume(msg));

     if (packetHeader.IsEncrypted())
     {
         ChipLogError(AppServer, "UDC encryption flag set - ignoring");
         return;
     }

     PayloadHeader payloadHeader;
     ReturnOnFailure(payloadHeader.DecodeAndConsume(msg));

     ChipLogProgress(AppServer, "IdentityDeclaration DataLength()=%d", msg->DataLength());

     uint8_t udcPayload[IdentificationDeclaration::kUdcTLVDataMaxBytes];
     size_t udcPayloadLength = std::min<size_t>(msg->DataLength(), sizeof(udcPayload));
     msg->Read(udcPayload, udcPayloadLength);

     IdentificationDeclaration id;
     id.ReadPayload(udcPayload, sizeof(udcPayload));

     if (id.GetCancelPasscode())
     {
         HandleUDCCancel(id);
         return;
     }

     if (id.GetCommissionerPasscodeReady())
     {
         HandleUDCCommissionerPasscodeReady(id);
         return;
     }

     HandleNewUDC(source, id);
 }

 void UserDirectedCommissioningServer::HandleNewUDC(const Transport::PeerAddress & source, IdentificationDeclaration & id)
 {
     char * instanceName = (char *) id.GetInstanceName();
     ChipLogProgress(AppServer, "HandleNewUDC instance=%s ", id.GetInstanceName());

     UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
     if (client == nullptr)
     {
         ChipLogProgress(AppServer, "UDC new instance state received");

         id.DebugLog();

         CHIP_ERROR err;
         err = mUdcClients.CreateNewUDCClientState(instanceName, &client);
         if (err != CHIP_NO_ERROR)
         {
             ChipLogError(AppServer, "UDC error creating new connection state");
             return;
         }

         if (id.HasDiscoveryInfo())
         {
             // if we received mDNS info, skip the commissionable lookup
             ChipLogDetail(AppServer, "UDC discovery info provided");
             mUdcClients.MarkUDCClientActive(client);

             client->SetUDCClientProcessingState(UDCClientProcessingState::kPromptingUser);
             client->SetPeerAddress(source);

             id.UpdateClientState(client);

             // Call the registered mUserConfirmationProvider, if any.
             if (mUserConfirmationProvider != nullptr)
             {
                 mUserConfirmationProvider->OnUserDirectedCommissioningRequest(*client);
             }
             return;
         }

         // Call the registered InstanceNameResolver, if any.
         if (mInstanceNameResolver != nullptr)
         {
             mInstanceNameResolver->FindCommissionableNode(instanceName);
         }
         else
         {
             ChipLogError(AppServer, "UserDirectedCommissioningServer::OnMessageReceived no mInstanceNameResolver registered");
         }
     }
     mUdcClients.MarkUDCClientActive(client);
 }

 void UserDirectedCommissioningServer::HandleUDCCancel(IdentificationDeclaration & id)
 {
     char * instanceName = (char *) id.GetInstanceName();
     ChipLogProgress(AppServer, "HandleUDCCancel instance=%s ", id.GetInstanceName());

     UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
     if (client == nullptr)
     {
         ChipLogProgress(AppServer, "UDC no matching instance found");
         return;
     }
     id.DebugLog();
     mUdcClients.MarkUDCClientActive(client);

     // Call the registered mUserConfirmationProvider, if any.
     if (mUserConfirmationProvider != nullptr)
     {
         mUserConfirmationProvider->OnCancel(*client);
     }

     // reset this entry so that the client can try again without waiting an hour
     client->Reset();
 }

 void UserDirectedCommissioningServer::HandleUDCCommissionerPasscodeReady(IdentificationDeclaration & id)
 {
     char * instanceName = (char *) id.GetInstanceName();
     ChipLogProgress(AppServer, "HandleUDCCommissionerPasscodeReady instance=%s ", id.GetInstanceName());

     UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
     if (client == nullptr)
     {
         ChipLogProgress(AppServer, "UDC no matching instance found");
         return;
     }
     if (client->GetUDCClientProcessingState() != UDCClientProcessingState::kWaitingForCommissionerPasscodeReady)
     {
         ChipLogProgress(AppServer, "UDC instance not in waiting for passcode ready state");
         return;
     }
     id.DebugLog();
     mUdcClients.MarkUDCClientActive(client);
     client->SetUDCClientProcessingState(UDCClientProcessingState::kObtainingOnboardingPayload);

     // Call the registered mUserConfirmationProvider, if any.
     if (mUserConfirmationProvider != nullptr)
     {
         mUserConfirmationProvider->OnCommissionerPasscodeReady(*client);
     }
 }

 CHIP_ERROR UserDirectedCommissioningServer::SendCDCMessage(CommissionerDeclaration cd, chip::Transport::PeerAddress peerAddress)
 {
     if (mTransportMgr == nullptr)
     {
         ChipLogError(AppServer, "CDC: No transport manager\n");
         return CHIP_ERROR_INCORRECT_STATE;
     }
     uint8_t idBuffer[IdentificationDeclaration::kUdcTLVDataMaxBytes];
     uint32_t length = cd.WritePayload(idBuffer, sizeof(idBuffer));
     if (length == 0)
     {
         ChipLogError(AppServer, "CDC: error writing payload\n");
         return CHIP_ERROR_INTERNAL;
     }

     chip::System::PacketBufferHandle payload = chip::MessagePacketBuffer::NewWithData(idBuffer, length);
     if (payload.IsNull())
     {
         ChipLogError(AppServer, "Unable to allocate packet buffer\n");
         return CHIP_ERROR_NO_MEMORY;
     }
     ReturnErrorOnFailure(EncodeUDCMessage(payload));

     cd.DebugLog();
     ChipLogProgress(Inet, "Sending CDC msg");

     auto err = mTransportMgr->SendMessage(peerAddress, std::move(payload));
     if (err != CHIP_NO_ERROR)
     {
         ChipLogError(AppServer, "CDC SendMessage failed: %" CHIP_ERROR_FORMAT, err.Format());
         return err;
     }

     ChipLogProgress(Inet, "CDC msg sent");
     return CHIP_NO_ERROR;
 }

 CHIP_ERROR UserDirectedCommissioningServer::EncodeUDCMessage(const System::PacketBufferHandle & payload)
 {
     PayloadHeader payloadHeader;
     PacketHeader packetHeader;

     payloadHeader.SetMessageType(MsgType::IdentificationDeclaration).SetInitiator(true).SetNeedsAck(false);

     VerifyOrReturnError(!payload.IsNull(), CHIP_ERROR_INVALID_ARGUMENT);
     VerifyOrReturnError(!payload->HasChainedBuffer(), CHIP_ERROR_INVALID_MESSAGE_LENGTH);
     VerifyOrReturnError(payload->TotalLength() <= kMaxAppMessageLen, CHIP_ERROR_MESSAGE_TOO_LONG);

     ReturnErrorOnFailure(payloadHeader.EncodeBeforeData(payload));

     ReturnErrorOnFailure(packetHeader.EncodeBeforeData(payload));

     return CHIP_NO_ERROR;
 }

 CHIP_ERROR IdentificationDeclaration::ReadPayload(uint8_t * udcPayload, size_t payloadBufferSize)
 {
     size_t i = 0;
     while (i < std::min<size_t>(sizeof(mInstanceName), payloadBufferSize) && udcPayload[i] != '\0')
     {
         mInstanceName[i] = (char) udcPayload[i];
         i++;
     }
     mInstanceName[i] = '\0';

     if (payloadBufferSize <= sizeof(mInstanceName))
     {
         ChipLogProgress(AppServer, "UDC - No TLV information in Identification Declaration");
         return CHIP_NO_ERROR;
     }
     // advance i to the end of the fixed length block containing instance name
     i = sizeof(mInstanceName);

     CHIP_ERROR err;

     TLV::TLVReader reader;
     reader.Init(udcPayload + i, payloadBufferSize - i);

     // read the envelope
     ReturnErrorOnFailure(reader.Next(chip::TLV::kTLVType_Structure, chip::TLV::AnonymousTag()));

     chip::TLV::TLVType outerContainerType = chip::TLV::kTLVType_Structure;
     ReturnErrorOnFailure(reader.EnterContainer(outerContainerType));

     while ((err = reader.Next()) == CHIP_NO_ERROR)
     {
         chip::TLV::Tag containerTag = reader.GetTag();
         if (!TLV::IsContextTag(containerTag))
         {
             ChipLogError(AppServer, "Unexpected non-context TLV tag.");
             return CHIP_ERROR_INVALID_TLV_TAG;
         }
         uint8_t tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));

         switch (tagNum)
         {
         case kVendorIdTag:
             // vendorId
             err = reader.Get(mVendorId);
             break;
         case kProductIdTag:
             // productId
             err = reader.Get(mProductId);
             break;
         case kCdPortTag:
             // port
             err = reader.Get(mCdPort);
             break;
         case kDeviceNameTag:
             // deviceName
             err = reader.GetString(mDeviceName, sizeof(mDeviceName));
             break;
         case kPairingInstTag:
             // pairingInst
             err = reader.GetString(mPairingInst, sizeof(mPairingInst));
             break;
         case kPairingHintTag:
             // pairingHint
             err = reader.Get(mPairingHint);
             break;
         case kRotatingIdTag:
             // rotatingId
             mRotatingIdLen = reader.GetLength();
             err            = reader.GetBytes(mRotatingId, sizeof(mRotatingId));
             break;
         case kTargetAppListTag:
             // app vendor list
             {
                 ChipLogProgress(AppServer, "TLV found an applist");
                 chip::TLV::TLVType listContainerType = chip::TLV::kTLVType_List;
                 ReturnErrorOnFailure(reader.EnterContainer(listContainerType));

                 while ((err = reader.Next()) == CHIP_NO_ERROR && mNumTargetAppInfos < sizeof(mTargetAppInfos))
                 {
                     containerTag = reader.GetTag();
                     if (!TLV::IsContextTag(containerTag))
                     {
                         ChipLogError(AppServer, "Unexpected non-context TLV tag.");
                         return CHIP_ERROR_INVALID_TLV_TAG;
                     }
                     tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));
                     if (tagNum == kTargetAppTag)
                     {
                         ReturnErrorOnFailure(reader.EnterContainer(outerContainerType));
                         uint16_t appVendorId  = 0;
                         uint16_t appProductId = 0;

                         while ((err = reader.Next()) == CHIP_NO_ERROR)
                         {
                             containerTag = reader.GetTag();
                             if (!TLV::IsContextTag(containerTag))
                             {
                                 ChipLogError(AppServer, "Unexpected non-context TLV tag.");
                                 return CHIP_ERROR_INVALID_TLV_TAG;
                             }
                             tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));
                             if (tagNum == kAppVendorIdTag)
                             {
                                 err = reader.Get(appVendorId);
                             }
                             else if (tagNum == kAppProductIdTag)
                             {
                                 err = reader.Get(appProductId);
                             }
                         }
                         if (err == CHIP_END_OF_TLV)
                         {
                             ChipLogProgress(AppServer, "TLV end of struct TLV");
                             ReturnErrorOnFailure(reader.ExitContainer(outerContainerType));
                         }
                         if (appVendorId != 0)
                         {
                             mTargetAppInfos[mNumTargetAppInfos].vendorId  = appVendorId;
                             mTargetAppInfos[mNumTargetAppInfos].productId = appProductId;
                             mNumTargetAppInfos++;
                         }
                     }
                     else
                     {
                         ChipLogError(AppServer, "unrecognized tag %d", tagNum);
                     }
                 }
                 if (err == CHIP_END_OF_TLV)
                 {
                     ChipLogProgress(AppServer, "TLV end of array");
                     ReturnErrorOnFailure(reader.ExitContainer(listContainerType));
                 }
             }
             break;
         case kNoPasscodeTag:
             err = reader.Get(mNoPasscode);
             break;
         case kCdUponPasscodeDialogTag:
             err = reader.Get(mCdUponPasscodeDialog);
             break;
         case kCommissionerPasscodeTag:
             err = reader.Get(mCommissionerPasscode);
             break;
         case kCommissionerPasscodeReadyTag:
             err = reader.Get(mCommissionerPasscodeReady);
             break;
         case kCancelPasscodeTag:
             err = reader.Get(mCancelPasscode);
             break;
         }
         if (err != CHIP_NO_ERROR)
         {
             ChipLogError(AppServer, "IdentificationDeclaration::ReadPayload read error %" CHIP_ERROR_FORMAT, err.Format());
         }
     }

     if (err == CHIP_END_OF_TLV)
     {
         // Exiting container
         ReturnErrorOnFailure(reader.ExitContainer(outerContainerType));
     }
     else
     {
         ChipLogError(AppServer, "IdentificationDeclaration::ReadPayload exiting early error %" CHIP_ERROR_FORMAT, err.Format());
     }

     ChipLogProgress(AppServer, "UDC TLV parse complete");
     return CHIP_NO_ERROR;
 }

 /**
  *  Reset the connection state to a completely uninitialized status.
  */
 uint32_t CommissionerDeclaration::WritePayload(uint8_t * payloadBuffer, size_t payloadBufferSize)
 {
     CHIP_ERROR err;

     chip::TLV::TLVWriter writer;

     writer.Init(payloadBuffer, payloadBufferSize);

     chip::TLV::TLVType outerContainerType = chip::TLV::kTLVType_Structure;
     VerifyOrExit(CHIP_NO_ERROR ==
                      (err = writer.StartContainer(chip::TLV::AnonymousTag(), chip::TLV::kTLVType_Structure, outerContainerType)),
                  LogErrorOnFailure(err));

     VerifyOrExit(CHIP_NO_ERROR == (err = writer.Put(chip::TLV::ContextTag(kErrorCodeTag), GetErrorCode())), LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kNeedsPasscodeTag), mNeedsPasscode)),
                  LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kNoAppsFoundTag), mNoAppsFound)),
                  LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR ==
                      (err = writer.PutBoolean(chip::TLV::ContextTag(kPasscodeDialogDisplayedTag), mPasscodeDialogDisplayed)),
                  LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kCommissionerPasscodeTag), mCommissionerPasscode)),
                  LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kQRCodeDisplayedTag), mQRCodeDisplayed)),
                  LogErrorOnFailure(err));

     VerifyOrExit(CHIP_NO_ERROR == (err = writer.EndContainer(outerContainerType)), LogErrorOnFailure(err));
     VerifyOrExit(CHIP_NO_ERROR == (err = writer.Finalize()), LogErrorOnFailure(err));

     ChipLogProgress(AppServer, "TLV write done");

     return writer.GetLengthWritten();

 exit:
     return 0;
 }

 void UserDirectedCommissioningServer::SetUDCClientProcessingState(char * instanceName, UDCClientProcessingState state)
 {
     UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
     if (client == nullptr)
     {
         CHIP_ERROR err;
         err = mUdcClients.CreateNewUDCClientState(instanceName, &client);
         if (err != CHIP_NO_ERROR)
         {
             ChipLogError(AppServer,
                          "UserDirectedCommissioningServer::SetUDCClientProcessingState error creating new connection state");
             return;
         }
     }

     ChipLogDetail(AppServer, "SetUDCClientProcessingState instance=%s new state=%d", StringOrNullMarker(instanceName), (int) state);

     client->SetUDCClientProcessingState(state);

     mUdcClients.MarkUDCClientActive(client);
 }

 void UserDirectedCommissioningServer::OnCommissionableNodeFound(const Dnssd::DiscoveredNodeData & nodeData)
 {
     if (nodeData.resolutionData.numIPs == 0)
     {
         ChipLogError(AppServer, "OnCommissionableNodeFound no IP addresses returned for instance name=%s",
                      nodeData.nodeData.instanceName);
         return;
     }
     if (nodeData.resolutionData.port == 0)
     {
         ChipLogError(AppServer, "OnCommissionableNodeFound no port returned for instance name=%s", nodeData.nodeData.instanceName);
         return;
     }

     UDCClientState * client = mUdcClients.FindUDCClientState(nodeData.nodeData.instanceName);
     if (client != nullptr && client->GetUDCClientProcessingState() == UDCClientProcessingState::kDiscoveringNode)
     {
         ChipLogDetail(AppServer, "OnCommissionableNodeFound instance: name=%s old_state=%d new_state=%d", client->GetInstanceName(),
                       (int) client->GetUDCClientProcessingState(), (int) UDCClientProcessingState::kPromptingUser);
         client->SetUDCClientProcessingState(UDCClientProcessingState::kPromptingUser);

 #if INET_CONFIG_ENABLE_IPV4
         // prefer IPv4 if its an option
         bool foundV4 = false;
         for (unsigned i = 0; i < nodeData.resolutionData.numIPs; ++i)
         {
             if (nodeData.resolutionData.ipAddress[i].IsIPv4())
             {
                 foundV4 = true;
                 client->SetPeerAddress(
                     chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[i], nodeData.resolutionData.port));
                 break;
             }
         }
         // use IPv6 as last resort
         if (!foundV4)
         {
             client->SetPeerAddress(
                 chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[0], nodeData.resolutionData.port));
         }
 #else  // INET_CONFIG_ENABLE_IPV4
        // if we only support V6, then try to find a v6 address
         bool foundV6 = false;
         for (unsigned i = 0; i < nodeData.resolutionData.numIPs; ++i)
         {
             if (nodeData.resolutionData.ipAddress[i].IsIPv6())
             {
                 foundV6 = true;
                 client->SetPeerAddress(
                     chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[i], nodeData.resolutionData.port));
                 break;
             }
         }
         // last resort, try with what we have
         if (!foundV6)
         {
             ChipLogError(AppServer, "OnCommissionableNodeFound no v6 returned for instance name=%s",
                          nodeData.nodeData.instanceName);
             client->SetPeerAddress(
                 chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[0], nodeData.resolutionData.port));
         }
 #endif // INET_CONFIG_ENABLE_IPV4

         client->SetDeviceName(nodeData.nodeData.deviceName);
         client->SetLongDiscriminator(nodeData.nodeData.longDiscriminator);
         client->SetVendorId(nodeData.nodeData.vendorId);
         client->SetProductId(nodeData.nodeData.productId);
         client->SetRotatingId(nodeData.nodeData.rotatingId, nodeData.nodeData.rotatingIdLen);

         // Call the registered mUserConfirmationProvider, if any.
         if (mUserConfirmationProvider != nullptr)
         {
             mUserConfirmationProvider->OnUserDirectedCommissioningRequest(*client);
         }
     }
 }

 void UserDirectedCommissioningServer::PrintUDCClients()
 {
     for (uint8_t i = 0; i < kMaxUDCClients; i++)
     {
         UDCClientState * state = GetUDCClients().GetUDCClientState(i);
         if (state == nullptr)
         {
             ChipLogProgress(AppServer, "UDC Client[%d] null", i);
         }
         else
         {
             char addrBuffer[chip::Transport::PeerAddress::kMaxToStringSize];
             state->GetPeerAddress().ToString(addrBuffer);

             char rotatingIdString[chip::Dnssd::kMaxRotatingIdLen * 2 + 1] = "";
             Encoding::BytesToUppercaseHexString(state->GetRotatingId(), chip::Dnssd::kMaxRotatingIdLen, rotatingIdString,
                                                 sizeof(rotatingIdString));

             ChipLogProgress(AppServer, "UDC Client[%d] instance=%s deviceName=%s address=%s, vid/pid=%d/%d disc=%d rid=%s", i,
                             state->GetInstanceName(), state->GetDeviceName(), addrBuffer, state->GetVendorId(),
                             state->GetProductId(), state->GetLongDiscriminator(), rotatingIdString);
         }
     }
 }

 } // namespace UserDirectedCommissioning
 } // namespace Protocols
 } // namespace chip
	/*
	*
	* Copyright (c) 2021-2022 Project CHIP Authors
	* All rights reserved.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/**
	* @file
	* This file implements an object for a Matter User Directed Commissioning unsolicited
	* recipient (server).
	*
	*/

	#include "UserDirectedCommissioning.h"
	#include <lib/core/CHIPSafeCasts.h>
	#include <system/TLVPacketBufferBackingStore.h>

	#include <unistd.h>

	namespace chip {
	namespace Protocols {
	namespace UserDirectedCommissioning {

	void UserDirectedCommissioningServer::OnMessageReceived(const Transport::PeerAddress & source, System::PacketBufferHandle && msg)
	{
	char addrBuffer[chip::Transport::PeerAddress::kMaxToStringSize];
	source.ToString(addrBuffer);
	ChipLogProgress(AppServer, "UserDirectedCommissioningServer::OnMessageReceived from %s", addrBuffer);

	PacketHeader packetHeader;

	ReturnOnFailure(packetHeader.DecodeAndConsume(msg));

	if (packetHeader.IsEncrypted())
	{
	ChipLogError(AppServer, "UDC encryption flag set - ignoring");
	return;
	}

	PayloadHeader payloadHeader;
	ReturnOnFailure(payloadHeader.DecodeAndConsume(msg));

	ChipLogProgress(AppServer, "IdentityDeclaration DataLength()=%d", msg->DataLength());

	uint8_t udcPayload[IdentificationDeclaration::kUdcTLVDataMaxBytes];
	size_t udcPayloadLength = std::min<size_t>(msg->DataLength(), sizeof(udcPayload));
	msg->Read(udcPayload, udcPayloadLength);

	IdentificationDeclaration id;
	id.ReadPayload(udcPayload, sizeof(udcPayload));

	if (id.GetCancelPasscode())
	{
	HandleUDCCancel(id);
	return;
	}

	if (id.GetCommissionerPasscodeReady())
	{
	HandleUDCCommissionerPasscodeReady(id);
	return;
	}

	HandleNewUDC(source, id);
	}

	void UserDirectedCommissioningServer::HandleNewUDC(const Transport::PeerAddress & source, IdentificationDeclaration & id)
	{
	char * instanceName = (char *) id.GetInstanceName();
	ChipLogProgress(AppServer, "HandleNewUDC instance=%s ", id.GetInstanceName());

	UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
	if (client == nullptr)
	{
	ChipLogProgress(AppServer, "UDC new instance state received");

	id.DebugLog();

	CHIP_ERROR err;
	err = mUdcClients.CreateNewUDCClientState(instanceName, &client);
	if (err != CHIP_NO_ERROR)
	{
	ChipLogError(AppServer, "UDC error creating new connection state");
	return;
	}

	if (id.HasDiscoveryInfo())
	{
	// if we received mDNS info, skip the commissionable lookup
	ChipLogDetail(AppServer, "UDC discovery info provided");
	mUdcClients.MarkUDCClientActive(client);

	client->SetUDCClientProcessingState(UDCClientProcessingState::kPromptingUser);
	client->SetPeerAddress(source);

	id.UpdateClientState(client);

	// Call the registered mUserConfirmationProvider, if any.
	if (mUserConfirmationProvider != nullptr)
	{
	mUserConfirmationProvider->OnUserDirectedCommissioningRequest(*client);
	}
	return;
	}

	// Call the registered InstanceNameResolver, if any.
	if (mInstanceNameResolver != nullptr)
	{
	mInstanceNameResolver->FindCommissionableNode(instanceName);
	}
	else
	{
	ChipLogError(AppServer, "UserDirectedCommissioningServer::OnMessageReceived no mInstanceNameResolver registered");
	}
	}
	mUdcClients.MarkUDCClientActive(client);
	}

	void UserDirectedCommissioningServer::HandleUDCCancel(IdentificationDeclaration & id)
	{
	char * instanceName = (char *) id.GetInstanceName();
	ChipLogProgress(AppServer, "HandleUDCCancel instance=%s ", id.GetInstanceName());

	UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
	if (client == nullptr)
	{
	ChipLogProgress(AppServer, "UDC no matching instance found");
	return;
	}
	id.DebugLog();
	mUdcClients.MarkUDCClientActive(client);

	// Call the registered mUserConfirmationProvider, if any.
	if (mUserConfirmationProvider != nullptr)
	{
	mUserConfirmationProvider->OnCancel(*client);
	}

	// reset this entry so that the client can try again without waiting an hour
	client->Reset();
	}

	void UserDirectedCommissioningServer::HandleUDCCommissionerPasscodeReady(IdentificationDeclaration & id)
	{
	char * instanceName = (char *) id.GetInstanceName();
	ChipLogProgress(AppServer, "HandleUDCCommissionerPasscodeReady instance=%s ", id.GetInstanceName());

	UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
	if (client == nullptr)
	{
	ChipLogProgress(AppServer, "UDC no matching instance found");
	return;
	}
	if (client->GetUDCClientProcessingState() != UDCClientProcessingState::kWaitingForCommissionerPasscodeReady)
	{
	ChipLogProgress(AppServer, "UDC instance not in waiting for passcode ready state");
	return;
	}
	id.DebugLog();
	mUdcClients.MarkUDCClientActive(client);
	client->SetUDCClientProcessingState(UDCClientProcessingState::kObtainingOnboardingPayload);

	// Call the registered mUserConfirmationProvider, if any.
	if (mUserConfirmationProvider != nullptr)
	{
	mUserConfirmationProvider->OnCommissionerPasscodeReady(*client);
	}
	}

	CHIP_ERROR UserDirectedCommissioningServer::SendCDCMessage(CommissionerDeclaration cd, chip::Transport::PeerAddress peerAddress)
	{
	if (mTransportMgr == nullptr)
	{
	ChipLogError(AppServer, "CDC: No transport manager\n");
	return CHIP_ERROR_INCORRECT_STATE;
	}
	uint8_t idBuffer[IdentificationDeclaration::kUdcTLVDataMaxBytes];
	uint32_t length = cd.WritePayload(idBuffer, sizeof(idBuffer));
	if (length == 0)
	{
	ChipLogError(AppServer, "CDC: error writing payload\n");
	return CHIP_ERROR_INTERNAL;
	}

	chip::System::PacketBufferHandle payload = chip::MessagePacketBuffer::NewWithData(idBuffer, length);
	if (payload.IsNull())
	{
	ChipLogError(AppServer, "Unable to allocate packet buffer\n");
	return CHIP_ERROR_NO_MEMORY;
	}
	ReturnErrorOnFailure(EncodeUDCMessage(payload));

	cd.DebugLog();
	ChipLogProgress(Inet, "Sending CDC msg");

	auto err = mTransportMgr->SendMessage(peerAddress, std::move(payload));
	if (err != CHIP_NO_ERROR)
	{
	ChipLogError(AppServer, "CDC SendMessage failed: %" CHIP_ERROR_FORMAT, err.Format());
	return err;
	}

	ChipLogProgress(Inet, "CDC msg sent");
	return CHIP_NO_ERROR;
	}

	CHIP_ERROR UserDirectedCommissioningServer::EncodeUDCMessage(const System::PacketBufferHandle & payload)
	{
	PayloadHeader payloadHeader;
	PacketHeader packetHeader;

	payloadHeader.SetMessageType(MsgType::IdentificationDeclaration).SetInitiator(true).SetNeedsAck(false);

	VerifyOrReturnError(!payload.IsNull(), CHIP_ERROR_INVALID_ARGUMENT);
	VerifyOrReturnError(!payload->HasChainedBuffer(), CHIP_ERROR_INVALID_MESSAGE_LENGTH);
	VerifyOrReturnError(payload->TotalLength() <= kMaxAppMessageLen, CHIP_ERROR_MESSAGE_TOO_LONG);

	ReturnErrorOnFailure(payloadHeader.EncodeBeforeData(payload));

	ReturnErrorOnFailure(packetHeader.EncodeBeforeData(payload));

	return CHIP_NO_ERROR;
	}

	CHIP_ERROR IdentificationDeclaration::ReadPayload(uint8_t * udcPayload, size_t payloadBufferSize)
	{
	size_t i = 0;
	while (i < std::min<size_t>(sizeof(mInstanceName), payloadBufferSize) && udcPayload[i] != '\0')
	{
	mInstanceName[i] = (char) udcPayload[i];
	i++;
	}
	mInstanceName[i] = '\0';

	if (payloadBufferSize <= sizeof(mInstanceName))
	{
	ChipLogProgress(AppServer, "UDC - No TLV information in Identification Declaration");
	return CHIP_NO_ERROR;
	}
	// advance i to the end of the fixed length block containing instance name
	i = sizeof(mInstanceName);

	CHIP_ERROR err;

	TLV::TLVReader reader;
	reader.Init(udcPayload + i, payloadBufferSize - i);

	// read the envelope
	ReturnErrorOnFailure(reader.Next(chip::TLV::kTLVType_Structure, chip::TLV::AnonymousTag()));

	chip::TLV::TLVType outerContainerType = chip::TLV::kTLVType_Structure;
	ReturnErrorOnFailure(reader.EnterContainer(outerContainerType));

	while ((err = reader.Next()) == CHIP_NO_ERROR)
	{
	chip::TLV::Tag containerTag = reader.GetTag();
	if (!TLV::IsContextTag(containerTag))
	{
	ChipLogError(AppServer, "Unexpected non-context TLV tag.");
	return CHIP_ERROR_INVALID_TLV_TAG;
	}
	uint8_t tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));

	switch (tagNum)
	{
	case kVendorIdTag:
	// vendorId
	err = reader.Get(mVendorId);
	break;
	case kProductIdTag:
	// productId
	err = reader.Get(mProductId);
	break;
	case kCdPortTag:
	// port
	err = reader.Get(mCdPort);
	break;
	case kDeviceNameTag:
	// deviceName
	err = reader.GetString(mDeviceName, sizeof(mDeviceName));
	break;
	case kPairingInstTag:
	// pairingInst
	err = reader.GetString(mPairingInst, sizeof(mPairingInst));
	break;
	case kPairingHintTag:
	// pairingHint
	err = reader.Get(mPairingHint);
	break;
	case kRotatingIdTag:
	// rotatingId
	mRotatingIdLen = reader.GetLength();
	err = reader.GetBytes(mRotatingId, sizeof(mRotatingId));
	break;
	case kTargetAppListTag:
	// app vendor list
	{
	ChipLogProgress(AppServer, "TLV found an applist");
	chip::TLV::TLVType listContainerType = chip::TLV::kTLVType_List;
	ReturnErrorOnFailure(reader.EnterContainer(listContainerType));

	while ((err = reader.Next()) == CHIP_NO_ERROR && mNumTargetAppInfos < sizeof(mTargetAppInfos))
	{
	containerTag = reader.GetTag();
	if (!TLV::IsContextTag(containerTag))
	{
	ChipLogError(AppServer, "Unexpected non-context TLV tag.");
	return CHIP_ERROR_INVALID_TLV_TAG;
	}
	tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));
	if (tagNum == kTargetAppTag)
	{
	ReturnErrorOnFailure(reader.EnterContainer(outerContainerType));
	uint16_t appVendorId = 0;
	uint16_t appProductId = 0;

	while ((err = reader.Next()) == CHIP_NO_ERROR)
	{
	containerTag = reader.GetTag();
	if (!TLV::IsContextTag(containerTag))
	{
	ChipLogError(AppServer, "Unexpected non-context TLV tag.");
	return CHIP_ERROR_INVALID_TLV_TAG;
	}
	tagNum = static_cast<uint8_t>(chip::TLV::TagNumFromTag(containerTag));
	if (tagNum == kAppVendorIdTag)
	{
	err = reader.Get(appVendorId);
	}
	else if (tagNum == kAppProductIdTag)
	{
	err = reader.Get(appProductId);
	}
	}
	if (err == CHIP_END_OF_TLV)
	{
	ChipLogProgress(AppServer, "TLV end of struct TLV");
	ReturnErrorOnFailure(reader.ExitContainer(outerContainerType));
	}
	if (appVendorId != 0)
	{
	mTargetAppInfos[mNumTargetAppInfos].vendorId = appVendorId;
	mTargetAppInfos[mNumTargetAppInfos].productId = appProductId;
	mNumTargetAppInfos++;
	}
	}
	else
	{
	ChipLogError(AppServer, "unrecognized tag %d", tagNum);
	}
	}
	if (err == CHIP_END_OF_TLV)
	{
	ChipLogProgress(AppServer, "TLV end of array");
	ReturnErrorOnFailure(reader.ExitContainer(listContainerType));
	}
	}
	break;
	case kNoPasscodeTag:
	err = reader.Get(mNoPasscode);
	break;
	case kCdUponPasscodeDialogTag:
	err = reader.Get(mCdUponPasscodeDialog);
	break;
	case kCommissionerPasscodeTag:
	err = reader.Get(mCommissionerPasscode);
	break;
	case kCommissionerPasscodeReadyTag:
	err = reader.Get(mCommissionerPasscodeReady);
	break;
	case kCancelPasscodeTag:
	err = reader.Get(mCancelPasscode);
	break;
	}
	if (err != CHIP_NO_ERROR)
	{
	ChipLogError(AppServer, "IdentificationDeclaration::ReadPayload read error %" CHIP_ERROR_FORMAT, err.Format());
	}
	}

	if (err == CHIP_END_OF_TLV)
	{
	// Exiting container
	ReturnErrorOnFailure(reader.ExitContainer(outerContainerType));
	}
	else
	{
	ChipLogError(AppServer, "IdentificationDeclaration::ReadPayload exiting early error %" CHIP_ERROR_FORMAT, err.Format());
	}

	ChipLogProgress(AppServer, "UDC TLV parse complete");
	return CHIP_NO_ERROR;
	}

	/**
	* Reset the connection state to a completely uninitialized status.
	*/
	uint32_t CommissionerDeclaration::WritePayload(uint8_t * payloadBuffer, size_t payloadBufferSize)
	{
	CHIP_ERROR err;

	chip::TLV::TLVWriter writer;

	writer.Init(payloadBuffer, payloadBufferSize);

	chip::TLV::TLVType outerContainerType = chip::TLV::kTLVType_Structure;
	VerifyOrExit(CHIP_NO_ERROR ==
	(err = writer.StartContainer(chip::TLV::AnonymousTag(), chip::TLV::kTLVType_Structure, outerContainerType)),
	LogErrorOnFailure(err));

	VerifyOrExit(CHIP_NO_ERROR == (err = writer.Put(chip::TLV::ContextTag(kErrorCodeTag), GetErrorCode())), LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kNeedsPasscodeTag), mNeedsPasscode)),
	LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kNoAppsFoundTag), mNoAppsFound)),
	LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR ==
	(err = writer.PutBoolean(chip::TLV::ContextTag(kPasscodeDialogDisplayedTag), mPasscodeDialogDisplayed)),
	LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kCommissionerPasscodeTag), mCommissionerPasscode)),
	LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR == (err = writer.PutBoolean(chip::TLV::ContextTag(kQRCodeDisplayedTag), mQRCodeDisplayed)),
	LogErrorOnFailure(err));

	VerifyOrExit(CHIP_NO_ERROR == (err = writer.EndContainer(outerContainerType)), LogErrorOnFailure(err));
	VerifyOrExit(CHIP_NO_ERROR == (err = writer.Finalize()), LogErrorOnFailure(err));

	ChipLogProgress(AppServer, "TLV write done");

	return writer.GetLengthWritten();

	exit:
	return 0;
	}

	void UserDirectedCommissioningServer::SetUDCClientProcessingState(char * instanceName, UDCClientProcessingState state)
	{
	UDCClientState * client = mUdcClients.FindUDCClientState(instanceName);
	if (client == nullptr)
	{
	CHIP_ERROR err;
	err = mUdcClients.CreateNewUDCClientState(instanceName, &client);
	if (err != CHIP_NO_ERROR)
	{
	ChipLogError(AppServer,
	"UserDirectedCommissioningServer::SetUDCClientProcessingState error creating new connection state");
	return;
	}
	}

	ChipLogDetail(AppServer, "SetUDCClientProcessingState instance=%s new state=%d", StringOrNullMarker(instanceName), (int) state);

	client->SetUDCClientProcessingState(state);

	mUdcClients.MarkUDCClientActive(client);
	}

	void UserDirectedCommissioningServer::OnCommissionableNodeFound(const Dnssd::DiscoveredNodeData & nodeData)
	{
	if (nodeData.resolutionData.numIPs == 0)
	{
	ChipLogError(AppServer, "OnCommissionableNodeFound no IP addresses returned for instance name=%s",
	nodeData.nodeData.instanceName);
	return;
	}
	if (nodeData.resolutionData.port == 0)
	{
	ChipLogError(AppServer, "OnCommissionableNodeFound no port returned for instance name=%s", nodeData.nodeData.instanceName);
	return;
	}

	UDCClientState * client = mUdcClients.FindUDCClientState(nodeData.nodeData.instanceName);
	if (client != nullptr && client->GetUDCClientProcessingState() == UDCClientProcessingState::kDiscoveringNode)
	{
	ChipLogDetail(AppServer, "OnCommissionableNodeFound instance: name=%s old_state=%d new_state=%d", client->GetInstanceName(),
	(int) client->GetUDCClientProcessingState(), (int) UDCClientProcessingState::kPromptingUser);
	client->SetUDCClientProcessingState(UDCClientProcessingState::kPromptingUser);

	#if INET_CONFIG_ENABLE_IPV4
	// prefer IPv4 if its an option
	bool foundV4 = false;
	for (unsigned i = 0; i < nodeData.resolutionData.numIPs; ++i)
	{
	if (nodeData.resolutionData.ipAddress[i].IsIPv4())
	{
	foundV4 = true;
	client->SetPeerAddress(
	chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[i], nodeData.resolutionData.port));
	break;
	}
	}
	// use IPv6 as last resort
	if (!foundV4)
	{
	client->SetPeerAddress(
	chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[0], nodeData.resolutionData.port));
	}
	#else // INET_CONFIG_ENABLE_IPV4
	// if we only support V6, then try to find a v6 address
	bool foundV6 = false;
	for (unsigned i = 0; i < nodeData.resolutionData.numIPs; ++i)
	{
	if (nodeData.resolutionData.ipAddress[i].IsIPv6())
	{
	foundV6 = true;
	client->SetPeerAddress(
	chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[i], nodeData.resolutionData.port));
	break;
	}
	}
	// last resort, try with what we have
	if (!foundV6)
	{
	ChipLogError(AppServer, "OnCommissionableNodeFound no v6 returned for instance name=%s",
	nodeData.nodeData.instanceName);
	client->SetPeerAddress(
	chip::Transport::PeerAddress::UDP(nodeData.resolutionData.ipAddress[0], nodeData.resolutionData.port));
	}
	#endif // INET_CONFIG_ENABLE_IPV4

	client->SetDeviceName(nodeData.nodeData.deviceName);
	client->SetLongDiscriminator(nodeData.nodeData.longDiscriminator);
	client->SetVendorId(nodeData.nodeData.vendorId);
	client->SetProductId(nodeData.nodeData.productId);
	client->SetRotatingId(nodeData.nodeData.rotatingId, nodeData.nodeData.rotatingIdLen);

	// Call the registered mUserConfirmationProvider, if any.
	if (mUserConfirmationProvider != nullptr)
	{
	mUserConfirmationProvider->OnUserDirectedCommissioningRequest(*client);
	}
	}
	}

	void UserDirectedCommissioningServer::PrintUDCClients()
	{
	for (uint8_t i = 0; i < kMaxUDCClients; i++)
	{
	UDCClientState * state = GetUDCClients().GetUDCClientState(i);
	if (state == nullptr)
	{
	ChipLogProgress(AppServer, "UDC Client[%d] null", i);
	}
	else
	{
	char addrBuffer[chip::Transport::PeerAddress::kMaxToStringSize];
	state->GetPeerAddress().ToString(addrBuffer);

	char rotatingIdString[chip::Dnssd::kMaxRotatingIdLen * 2 + 1] = "";
	Encoding::BytesToUppercaseHexString(state->GetRotatingId(), chip::Dnssd::kMaxRotatingIdLen, rotatingIdString,
	sizeof(rotatingIdString));

	ChipLogProgress(AppServer, "UDC Client[%d] instance=%s deviceName=%s address=%s, vid/pid=%d/%d disc=%d rid=%s", i,
	state->GetInstanceName(), state->GetDeviceName(), addrBuffer, state->GetVendorId(),
	state->GetProductId(), state->GetLongDiscriminator(), rotatingIdString);
	}
	}
	}

	} // namespace UserDirectedCommissioning
	} // namespace Protocols
	} // namespace chip